The present invention relates to catheters, and more particularly, to a double endobronchial catheter that is used to isolate one lung of a patient during anesthesia and surgery.
There are many operations that are carried out or performed today on a patient that require one lung of that patient to be isolated, that is, one of the patient""s lungs must be kept relatively immobilized during the operation so that the surgery can be performed. Typical of such operations include thoracoscopic lung surgery, minor or major lung resection, thoracic aorta repair or reconstruction, esophageal surgery and anterior thoracic spine surgery.
The need to isolate such lungs in order to operate stem from the very nature of a surgical operation performed under general anesthesia. In such operations, an anesthesia apparatus actually breathes for the patient by means of an anesthesia ventilator that acts in conjunction with an anesthesia machine. The anesthesia ventilator provides a timed, intermittent flow of gas to the patient to force that gas into the patient to expand the lungs, while the gas is expelled from the lungs as the lungs deflate. The anesthesia machine adds the anesthetic, in the form of a vapor, to the gas so that the anesthetic laden gas is provided to the patient to carry out the induction and maintenance of anesthesia in the patient during the operation. Thus under normal operation, both lungs are continually expanded and contracted during the inhalation and exhalation of the anesthetic laden gases in accordance with the normal cycling of the anesthesia ventilator.
Obviously, with the aforelisted operations where it is undesirable to have one of the lungs in motion, it becomes necessary to isolate that lung for the entire operation so that it is not subject to the normal expansion and contraction that is caused by the anesthesia ventilator. Therefore, the lung to be operated on is normally isolated by occluding the bronchus of that lung such that the anesthesia machine breathes the anesthetic laden gas into and from the other lung without affecting the lung subject to the operation. Thus the patient can be anesthetized and the operation can be carried out on the isolated lung. One of the difficulties, however, is to fully and effectively occlude the mainstream bronchus leading into the lung that is to be subject to the surgery.
One of the more common techniques currently used to provide the necessary isolation for one lung is through the use of a double lumen endotracheal tube. With the use of a double lumen endotracheal tube, however, there are certain drawbacks to its use.
In particular, there can be a considerable drawback in its insertion in the event of an unanticipated difficult airway visualization or the presence of a paralyzed vocal cord. Further, the anesthesiologist may choose to abandon the use of a double endotracheal tube in the event some anatomical problem is encountered in its placement, such as tracheal narrowing, which could preclude the proper positioning of the double lumen endotracheal tube. In addition, with many procedures, there is a difficult situation where the risk of gastric aspiration is high and a double lumen endotracheal tube needs to be replaced by a standard single lumen tube after the conclusion of the operation.
Thus, in accordance with the present invention, there is provided a double endobronchial catheter that is relatively easy to use with a patient and yet which provides effective isolation of a single lung of the patient so that surgery can be performed on that lung without interference caused by movement of that lung during the normal general anesthesia involving the ventilation of the lung.
With the present invention, there is an outer sheath that can be intubated into the trachea of the patient either external to a standard single lumen endotracheal tube or embodied within it and which outer sheath has a plurality of individual lumens formed therein. In the preferred embodiment, there are but two lumens within the outer sheath and they are formed by being molded into the outer sheath with an integrally molded divider separating the individual lumens. Within each of those two lumens there is positioned a catheter that is free to slide within the individual lumens of the outer sheath. In order to allow ease of movement within the lumens of the outer sheath, the outer surfaces of each catheter is preferably coated with a lubricious material, such as silicone. At the distal end of both of the catheters, there is an inflatable balloon and an inflation passage is provided so that each balloon can be individually inflated by the user by means of an inflation device at or near the proximal end of each catheter.
The individual catheters are flexible and can be manipulated by the user proximal to the patient after intubation of the outer sheath and a stylet can be associated with each catheter that passes through each of the catheters to aid in the manipulation of the individual catheters. In the preferred embodiment, the stylets are removable from the catheter after the proper positioning of the catheters.
Each of the catheters also includes a suction passageway that comprises a means of applying suction at the distal end of the catheters by a vacuum source or system connected to the proximal end of the catheters so that suction can be applied to a lung as desired.
In accordance with the present invention, there is provided a double endobronchial catheter that can be used in many instances where the prior art double lumen endotracheal tube is not appropriate or feasible. For example, the present invention can be a smaller device than the current double lumen endotracheal tube and thus can be used where a double endotracheal tube cannot be intubated through the vocal cords because of unanticipated difficult airway visualization or the presence of a paralyzed vocal cord. Too, the present invention can be used if the physician encounters lower airway anatomical problems, such as narrowing of the passageways, that would otherwise preclude the use of a double lumen endotracheal tube. Further, in the event of a patient who cannot open the mouth well or one with a known difficult intubation so as to make the placement of a double lumen endotracheal tube difficult, the present invention can be used in an xe2x80x9cawake fiberoptic intubationxe2x80x9d using a single lumen endotracheal tube followed by the use of the present double endobronchial catheter.
Also, due to the presence of through orifices in the catheters used with the present invention, in cases where selective lobar blockade is desired (partial one-lung collapse), the present double endobronchial catheter can be used and later the lung converted to full collapse if so desired. Partial collapse may be chosen in patients with marginal pulmonary function reserve prior to surgery that will not tolerate full collapse.
In addition, the present double endobronchial catheter can be made with smaller, softer, lower pressure balloons than those found on the present single or double lumen endotracheal tubes and thus can be used where intubation of the former tubes is difficult due to the anatomy of the patient. Too, with the use of the present invention, there is no need to replace a double lumen endotracheal tube with a single lumen endotracheal tube and thus the risk of aspiration is virtually eliminated where caused by that action.
Other features of the overall endobronchial catheter will become more apparent in light of the following detailed description of a preferred embodiment thereof and as illustrated in the accompanying drawings.